Processing uplink signals in high speed scenario

Abstract

A network node is connected to a plurality of antenna nodes that are located along a path where a plurality of wireless communication devices are located. The antenna nodes are controlled ( 302 ) to maintain reception radio lobes substantially along the path such that the wireless communication devices can communicate with the network node via the reception radio lobes. From a detected ( 304 ) radio frequency signal, a determination ( 306 ) is made that a UE belongs to a group of UEs having common Doppler radio frequency characteristics. This determination then enables processing ( 308 ) of the received signal involving the common Doppler characteristics.

The invention claimed is: 
     
       1. A method performed by a network node, where the network node is connected to a plurality of antenna nodes that are located along a path where a plurality of wireless communication devices are located, the method comprising:
 controlling the plurality of antenna nodes to maintain reception radio lobes substantially along the path such that the plurality of wireless communication devices can communicate with the network node via the reception radio lobes; 
 detecting a radio frequency (RF) signal; 
 determining that the detected RF signal originates from a wireless communication device of a specific subset among said plurality of wireless communication devices, said specific subset comprising wireless communication devices that are associated with a common Doppler radio frequency characteristic; and 
 processing the detected RF signal, said processing comprising a utilization of said Doppler radio frequency characteristic that is associated with said specific subset of wireless communication devices. 
 
     
     
       2. The method of  claim 1 , wherein the determination that the detected RF signal originates from the wireless communication device of the specific subset comprises analyzing the detected RF signal in terms of at least a frequency envelope. 
     
     
       3. The method of  claim 1 , wherein the determination that the detected RF signal originates from the wireless communication device of the specific subset comprises utilizing a-priori information available to the network node. 
     
     
       4. The method of  claim 1 , comprising:
 determining a respective motion value representative of motion of at least one subset of wireless communication devices; 
 calculating, based on said respective motion value, a respective Doppler radio frequency characteristic that is representative of said at least one subset of wireless communication devices; and 
 associating said respective Doppler radio frequency characteristic with said at least one subset of wireless communication devices. 
 
     
     
       5. The method of  claim 4 , wherein the determination of the respective motion value comprises determining a forward motion value representative of motion, in a forward direction along the path, of a forward moving subset of wireless communication devices. 
     
     
       6. The method of  claim 4 , wherein the determination of the respective motion value comprises determining a reverse motion value representative of motion, in a reverse direction opposite a forward direction along the path, of a reverse moving subset of wireless communication devices. 
     
     
       7. The method of  claim 4 , wherein the determination of the respective motion value comprises determining a third motion value representative of non-motion of a non-moving subset of wireless communication devices. 
     
     
       8. The method of  claim 4 , wherein the determination of the respective motion value comprises obtaining the respective motion value from predetermined information available to the network node, said predetermined information comprising information associated with geographic locations of the plurality of antenna nodes in relation to the path. 
     
     
       9. The method of  claim 4 , wherein the determination of the respective motion value comprises analyzing detected RF signals, comprising an analysis of frequency characteristics. 
     
     
       10. The method of  claim 1 , wherein the processing of the detected RF signal comprises frequency compensating during physical random access channel (PRACH) detection by any of:
 frequency translation prior to demodulation, and 
 rotation of PRACH sequences. 
 
     
     
       11. The method of  claim 1 , wherein the processing of the detected RF signal comprises frequency compensating during processing of any of physical uplink control channel (PUCCH) and physical uplink shared channel (PUSCH) by any of:
 frequency offset compensation prior to demodulation, and 
 frequency offset compensation subsequent to demodulation. 
 
     
     
       12. A network node configured to be connected to a plurality of antenna nodes that are located along a path where a plurality of wireless communication devices are located, the network node comprising input/output circuitry, a processor and a memory, said memory containing instructions executable by said processor whereby said network node is operative to:
 control the plurality of antenna nodes to maintain reception radio lobes substantially along the path such that the plurality of wireless communication devices can communicate with the network node via the reception radio lobes; 
 detect a radio frequency (RF) signal; 
 determine that the detected RF signal originates from a wireless communication device of a specific subset among said plurality of wireless communication devices, said specific subset comprising wireless communication devices that are associated with a common Doppler radio frequency characteristic; and 
 process the detected RF signal, said processing comprising a utilization of said Doppler radio frequency characteristic that is associated with said specific subset of wireless communication devices. 
 
     
     
       13. The network node of  claim 12 , wherein the processor and memory are configured such that the determination that the detected RF signal originates from the wireless communication device of the specific subset comprises analyzing the detected RF signal in terms of at least a frequency envelope. 
     
     
       14. The network node of  claim 12 , wherein the processor and memory are configured such that the determination that the detected RF signal originates from the wireless communication device of the specific subset comprises utilizing a-priori information available to the network node. 
     
     
       15. The network node of  claim 12 , wherein the processor and memory are configured to:
 determine a respective motion value representative of motion of at least one subset of wireless communication devices; 
 calculate, based on said respective motion value, a respective Doppler radio frequency characteristic that is representative of said at least one subset of wireless communication devices; and 
 associate said respective Doppler radio frequency characteristic with said at least one subset of wireless communication devices. 
 
     
     
       16. The network node of  claim 15 , wherein the processor and memory are configured such that the determination of the respective motion value comprises determining a forward motion value representative of motion, in a forward direction along the path, of a forward moving subset of wireless communication devices. 
     
     
       17. The network node of  claim 15 , wherein the processor and memory are configured such that the determination of the respective motion value comprises determining a reverse motion value representative of motion, in a reverse direction opposite a forward direction along the path, of a reverse moving subset of wireless communication devices. 
     
     
       18. The network node of  claim 15 , wherein the processor and memory are configured such that the determination of the respective motion value comprises determining a third motion value representative of non-motion of a non-moving subset of wireless communication devices. 
     
     
       19. The network node of  claim 15 , wherein the processor and memory are configured such that the determination of the respective motion value comprises:
 obtaining the respective motion value from predetermined information available to the network node, said predetermined information comprising information associated with geographic locations of the plurality of antenna nodes in relation to the path. 
 
     
     
       20. The network node of  claim 15 , wherein the processor and memory are configured such that the determination of the respective motion value comprises analyzing detected RF signals, comprising an analysis of frequency characteristics. 
     
     
       21. The network node of  claim 12 , wherein the processor and memory are configured such that the processing of the detected RF signal comprises frequency compensating during physical random access channel (PRACH) detection by any of:
 frequency translation prior to demodulation, and 
 rotation of PRACH sequences. 
 
     
     
       22. The network node of  claim 12 , wherein the processor and memory are configured such that the processing of the detected RF signal comprises frequency compensating during processing of any of physical uplink control channel (PUCCH) and physical uplink shared channel (PUSCH) by any of:
 frequency offset compensation prior to demodulation, and 
 frequency offset compensation subsequent to demodulation. 
 
     
     
       23. A non-transitory computer-readable medium comprising, stored thereupon, a computer program comprising instructions that, when executed on at least one processor in a network node that is connected to a plurality of antenna nodes that are located along a path where a plurality of wireless communication devices are located, cause the network node to:
 control the plurality of antenna nodes to maintain reception radio lobes substantially along the path such that the plurality of wireless communication devices can communicate with the network node via the reception radio lobes; 
 detect a radio frequency (RF) signal; 
 determine that the detected RF signal originates from a wireless communication device of a specific subset among said plurality of wireless communication devices, said specific subset comprising wireless communication devices that are associated with a common Doppler radio frequency characteristic; and 
 process the detected RF signal, said processing comprising a utilization of said Doppler radio frequency characteristic that is associated with said specific subset of wireless communication devices.